1. Field of The Invention
The present invention is related to automotive test apparatus and, more particularly, is directed towards means for permitting the precise determination of the existence and location of fractures in the cylinder head of an engine.
2. Description of The Prior Art
It is known that cylinder heads of internal combustion engines may crack or fracture under excessive heat conditions. Recently, the cylinder heads of diesel engines, in particular, have been experiencing a high degree of fractures and cracks, which have been the result of increased power in such engines through the use of superchargers and the like which have, in turn, resulted in extreme heat conditions being imposed on the engine.
Generally, the cracks and fractures are minute, and are therefore impossible to detect by the human eye. It is known in the art to test such cylinder heads for the existence of minute fractures and cracks by subjecting them to a high pressure testing procedure.
In this procedure, the cylinder head is first dismantled from the cylinder block. The cylinder head itself contains a plurality of interconnected water conduits which conduct coolant through the head during normal operation. During testing for cracks and fractures, the water channels and conduits are grouped in sets, and each set is sealed by a single large gasket and cover member, while water under pressure is applied to one of the water channels that serves as an inlet conduit. The operator then visually inspects the head for water leakage, which would be indicative of a crack or fracture.
One problem with the prior art testing apparatus described above is that the unduly large cover and gasket for each set of water conduits can prevent detection of the existence of a fracture in the areas between the water conduits within a set, i.e., the area under the cover and gasket. In this case, the gasket tends to act as a seal to prevent any leakage from being detected.
If in fact there exists a fracture, and it goes undetected, the engine when put back in service can suffer very extensive damage as a result of water commingling with the oil.
Additionally, with the prior art apparatus, even if a fracture or crack under the gasket and cover member is detected, it is impossible to determine the precise location of the fracture in order that it might be repaired.
It may be appreciated from the foregoing that a great need exists for an inexpensive, easy to use apparatus for positively determining both the existence and location of minute fractures in engine cylinder heads.
United States patents in this general area area of which I am aware include the Wilkinson U.S. Pat. No. 3,608,369 and the Durgan et al U.S. Pat. No. 3,973,429. The latter patent teaches a rather complicated testing apparatus for engine heads which is designed to accommodate virtually any internal combustion head on the market for testing purposes. The former patent teaches an engine head test stand which includes a support plate having sealer elements which are adapted to be received in openings in the engine head.
However, neither of the foregoing references solve the problem towards which the present invention is advanced in an economical manner.